This disclosure relates to gesture recognition.
Computers, game consoles, personal digital assistants, and other information appliances typically include some type of user interface through which inputs and outputs pass.
Inputs from the user are often delivered through a cable from a keyboard, a mouse, a joystick, or other controller. The user actuates keys, buttons, or other switches included on the controller in order to provide input to the information appliance. The action a user takes in order to provide input to an information appliance, such as pressing a button, is referred to here as an “input action.”
In some applications, it may be desirable for an input action to be driven by a particular human gesture. Specialized input devices can be used in such applications so that the user can provide command and control inputs by performing a particular gesture in direct physical contact with the input device. For example, in a dance competition game, the game prompts the user to “perform” various dance moves. A pressure sensitive pad is typically provided so that the user can perform a dance move by tapping a specified portion of the pressure sensitive pad with one of the user's feet. In this way, the input action (that is, tapping a portion of the pressure sensitive pad) captures an aspect of a dance move. Another example is a music creation program in which a user can hit a MIDI drum pad with drumsticks in order to simulate playing the drums.
Other approaches to supplying input to an information appliance may make use of gesture recognition technology. In one approach, motion capturing sensors, e.g, body suits or gloves are attached to the user to measure the user's movements. These measurements are then used to determine the gesture that the user is performing. These devices are often expensive and intrusive. Gesture recognition makes use of pattern recognition technology. Generally, such an approach involves capturing video of a user performing various actions, temporally segmenting the video into video clips containing discrete gestures, and then determining if each video clip contains a predefined gesture from a gesture vocabulary. For example, one potential application of such gesture recognition technology is to recognize gestures from the American Sign Language. Such gesture recognition technology typically requires the video to be manually segmented into video clips, which makes such conventional gesture recognition technology less than fully automatic.